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I always trusted Cat Eye and ended up getting the Cat Eye 7 cordless. I set it up exactly as they say to but when speed picks up quickly the computer goes backwards before advancing the speed reading! damn it! there is no adjustment I have found to keep this from happening, even if I spin the front wheel, it will show 10, then drop to 2 back up to 9.9, then 9.8 and back down to 4 then back up to 9.7. I am about ready to see how far I can throw this POS but thought Id ask you guys first. Thanks in advance!

yeah, that sounds weird. it's like the magnet is missing the receiver (not the computer, the thing on the fork) for one revolution but hitting it the rest of the time. the time it misses the receiver the speed will drop down, for obvious reasons, then it hits the next time spiking it back up to speed.

i always end up readjusting my magnet and reciever every couple of weeks.

yeah, that sounds weird. it's like the magnet is missing the receiver (not the computer, the thing on the fork) for one revolution but hitting it the rest of the time. the time it misses the receiver the speed will drop down, for obvious reasons, then it hits the next time spiking it back up to speed.

i always end up readjusting my magnet and reciever every couple of weeks.

thanks but I tried that idea, I have it so close to the transmiter its almost hitting as it spins around. Im wondering if the transmiter battery could be weak and sending a signal that cant ramp up fast enough? Just a guess. Probably should get my sore butt up and get the multi meter out and check the battery voltage?

Some other things to consider are the distance from the transmitter to your handlebar unit, and is there a clear unobstructed line between your transmitter and receiver? By this I mean that your handlebar unit is on the same side of the stem/fork as the transmitter (speed sensor).

I have had nothing but trouble with a Sigma sport wireless. The mounting system for the transmitter is hump! However, my Flightdeck wireless on another bike is superb. i am swapping to a Flightdeck on the other bike too.

I have never noticed a problem with CatEye sensors giving erroneous readings like that but I also haven't used a CateEye wireless sensor. The wireless sensor for my Shimano FlightDeck doesn't exhibit that behaviour. It does have its own share of issues though that seem to stem around being succeptable to random EM spewing off traffic sensors at intersections but I understand that a lot of sensors have that problem, wireless or not.

Some wheel sensors use a mechanical reed-switch that gets tripped by a magnetic field. I suppose that switch could get "stuck" if the second-order flux is happening too fast for it to release and return quick enough to provide a descriminating pulse which could fool the computer into missing a revolution thus give the impression of a deceleration.

I have never noticed a problem with CatEye sensors giving erroneous readings like that but I also haven't used a CateEye wireless sensor. The wireless sensor for my Shimano FlightDeck doesn't exhibit that behaviour. It does have its own share of issues though that seem to stem around being succeptable to random EM spewing off traffic sensors at intersections but I understand that a lot of sensors have that problem, wireless or not.

Some wheel sensors use a mechanical reed-switch that gets tripped by a magnetic field. I suppose that switch could get "stuck" if the second-order flux is happening too fast for it to release and return quick enough to provide a descriminating pulse which could fool the computer into missing a revolution thus give the impression of a deceleration.

I think you're the only person I know who uses the term "second-order flux" when talking about a freaking bike computer. Well my flux capacitor is bigger than your flux capacitor!

VEGANRIDER: make sure you're not near anything that can produce any type of EM interference.

I always trusted Cat Eye and ended up getting the Cat Eye 7 cordless. I set it up exactly as they say to but when speed picks up quickly the computer goes backwards before advancing the speed reading! damn it! there is no adjustment I have found to keep this from happening, even if I spin the front wheel, it will show 10, then drop to 2 back up to 9.9, then 9.8 and back down to 4 then back up to 9.7. I am about ready to see how far I can throw this POS but thought Id ask you guys first. Thanks in advance!

Mine had the same problem as your's. I thought I got ahold of a bad computer so I bought another one (got a really good deal on it). But it also has the same problem. I started a thread in the road bike forum yesterday asking for recommendations for a new one cause I am going to take a sledge hammer to this P.O.S . Good luck on finding a new one.

Mine had the same problem as your's. I thought I got ahold of a bad computer so I bought another one (got a really good deal on it). But it also has the same problem. I started a thread in the road bike forum yesterday asking for recommendations for a new one cause I am going to take a sledge hammer to this P.O.S . Good luck on finding a new one.

We had a few customers come into our shop with the same problem. We called CatEye and they said they had a batch of computers go out with bad transmitters. The sent us a bunch of new ones for all the ones we had issues with. It seemed to fix the problem for the customers I dealt with so I would give CatEye and a call and see if they'll hook you up.